This application claims the priority of Korean Patent Application No. 2003-48436, filed on Jul. 15, 2003, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a wake disturbing apparatus and method for reducing drag, which can considerably reduce drag caused by a significant decrease in the pressure behind an object with a blunt trailing edge, such as a vehicle, while the object is traveling at high speed.
2. Description of the Related Art
In general, large vehicles, such as a heavy vehicle and a bus consume about 60% of their energy through aerodynamic drag. For example, in a case where a heavy vehicle travels 100 kilometers an hour, air resistance is accountable for 60% of its total energy consumption.
Such aerodynamic drag often occurs due to pressure at a rear part of an object (hereinafter, this part is referred to as ‘base surface’) while the object is traveling at high speed. The drag on the object can be reduced by decreasing the strength of vortical motion around the base surface and thus recovering pressure there, which has been decreased due to the strong vortical motion of the wake.
There have been many attempts to increase pressure at the base surface, but most of them cannot be realized and commercialized because they require the shape of the object to be significantly changed into, for example, a streamlined one, or they need much more energy than they can save by reducing the aerodynamic drag.